Private Browsing

I understand what is meant by Private Browsing, but I can't help thinking that the term should be used for a different purpose: We should be able to keep our requests for page loading, information, etc free from trackers, cookies, etc. Extensions can help to some degree - Ghostery, etc - but how well does it really work? Similarly ad blocking is not overly effective - just look at http://www.macupdate.com/ or http://www.theweathernetwork.com/weather/canada/ontario/hanover So, maybe if Vivaldi had something built in, it would help. Vivaldi does have a Page Action called "Content Blocker" but I have not noticed it blocking anything - perhaps it is not yet ready?

By now, the "Private window"/"private tab" terminology has already become pretty established across most browser makers as meaning no more than just "private from other people accessing the same computer account" (i.e. just having a browsing session isolated from existing cookies and with no history/cookie persistence once closed), so I doubt that usage is going anywhere in Vivaldi.
For the moment, what you're describing can be done to some extent with an extension like uBlock Origin, uBlock, ABP, etc. I don't know if Vivaldi plans to have include built in content-blocking or not, the way Presto Opera had it on right-click.
As for how well those work, it depends on what you're hoping to avoid and just how paranoid you want/need to be; depending on whom you're worried about, privacy can have many different meanings. The aforementioned extensions can black known ad or tracking networks, but by the very nature of how the web works, sites are still free to log whatever IP address they see, note usage patterns, etc. (There are things like [Tor](https://en.wikipedia.org/wiki/Tor_(anonymity_network)), but even that has weaknesses, and I doubt Vivaldi is going to bother baking that in.)